This invention relates to core puller assemblies for molds used in conjunction with concrete block machines, and particularly to a rapid-acting, automatic multiple cylinder assembly.
High production concrete block machines operate rapidly and in those instances in which multiple blocks are molded with grooved lower faces it is necessary to provide multiple core bars which can be retracted from the molds at high speed to permit the newly molded blocks to be stripped from the molds and lowered by pallet onto a conveyor for transportation to storage.
In the past, core pullers have been utilized which provide a single, heavy duty hydraulic ram having a header actuated by the hydraulic ram and carrying multiple core bars which are inserted into, and retracted from, the molds. Such core pullers are heavy and bulky and cause serious space problems. In general, they are custom manufactured to suit a particular block machine and are not readily adapted for use with other block machines.
Machines of this type tend to be subject to guidance problems with respect to the elongate core bars and also to vibration problems resulting from intense vibration of the block machine during the molding process. Further, the use of a single hydraulically operated ram results in a relatively slow acting core puller assembly which interferes with normal production.
The present core puller solves these and other problems in a manner not disclosed in the known prior art.